1. Field of the Invention
The present invention relates to a tool for dispensing one- or multi-component masses contained in cartridges or foil bags and which includes a housing, at least one handle provided on the housing, at least one piston rod displaceable in the housing, a displacement mechanism for displacing the at least one piston rod and having at least one displacement member and a locking member which are arranged on the at least one piston rod, are axially displaceable, and are pivotable in a longitudinal direction of the tool, a force transmission device acting on the displacement member, and at least one actuation member for actuating the force transmission device.
2. Description of the Prior Art
One- or multi-component chemical masses are used for different purposes as mortar, glue, or sealing masses in constructions, vehicles, aircrafts, ships, machines, and numerous other apparatuses. Conventionally, the masses are supplied to users in foil bags or cartridges. The foil bags or cartridges are placed in corresponding tools, and the masses are dispensed therefrom.
Suitable dispensing tools have, e.g., mechanical displacement mechanisms for displacing a piston rod that provides for forcing the mass out. German publication DE 36 07 384 A1 discloses a tool for displacing one- or multi-component masses from foil bags and cartridges and including a housing with a handle, a piston rod for forcing the mass out and which is displaceable by a displacement mechanism. The displacement mechanism has a displacement member and a locking member which are arranged on the piston rod, are axially displaceable, and pivot in the longitudinal direction of the tool between two end stops. On the handle, there is provided an actuation member upon actuation of which, a force transmitting element, which is formed as a multi-arm lever, acts on the displacement member, pivoting the same. The piston rod is displaced in the dispensing direction in accordance with the available lever path. The locking member prevents an undesirable movement of the piston rod in the opposite direction, i.e., in the direction opposite the dispensing direction. A release lever can so pivot the locking member that the piston rod would return to its initial position.
German Publication DE 42 31 418 A1 disclosed another tool for dispensing one- or multi-component masses contained in foil bags or cartridge and in which the actuation member is formed as a two-arm lever, with one arm of the lever acting directly on the displacement member for displacing the piston rod upon actuation of the lever.
Mechanical tools are characterized, in particular, by a low susceptibility to interference. These tools are easily handled and can be used in different applications. The drawback of the known tools consists in that for glutinous one- or multi-components masses which are located in the tools, for actuation, application of a large force is necessary, so that with a lasting operation, the user becomes tired. In addition, with actuation levers, the transmission ratios are low. If, e.g., very large forces with a short displacement path should be realized with the actuation member, the second lever length in, e.g., DE 42 31 418 A1 should be very small. With such a lever, the force application point lies close to the rotational axis of the lever.
Because of the mechanical design of the force transmission device, the arrangement of the lever is predetermined. Dependent on type and weight of a dispensable foil bag or cartridge and on a further use of the residual amount of the dispensed masses, the weight ratios of the dispensing tools change, and the tools are not any more in an equilibrium. As a result, an unbalanced, e.g. top heavy tool leads during a lasting operation to fatigue of the user.
In addition to mechanical tools, pneumatic tools for dispensing of one- or multi-component masses, which are contained in foil bags or cartridges, are known. German Publication DE 40 32 349 A1 discloses such a pneumatic tool in which a piston rod, which is displaceable in a hollow cylinder, is displaced by compressing air for dispensing a dispensable mass. The drawback of the tool of DE 40 32 349 A1 consists in that because of numerous seals and constructive elements, the tool has a certain tendency to fail. Further, for operating a pneumatic tool, an external source of compressed air must be available.
Also known are hydraulic tools for dispensing one- or multi-component masses contained in foil bags or cartridges. German Publication DE 42 29 956 A1 discloses a hydraulic tool for dispensing a mass from a foil bag in which a dispensing piston is displaced by a pressure fluid upon actuation of an actuation member provided on the handle. This tool likewise is prone to failure because of numerous seals and constructive elements.
Accordingly, an object of the present invention is to provide a tool for dispensing one- or multi-component masses contained in the foil bags in which the above-mentioned drawbacks of known tools are eliminated and which remains user-friendly even during a lasting operation.